Efficient modeling of apertures in thin conducting screens by the TLM method

The shielding effectiveness of enclosures used in EMC is often determined by apertures. Mostly these apertures are small compared to the wavelength and the enclosure's dimensions. The modeling with numerical field calculation methods can therefore be difficult. This paper presents the extension of the transmission line matrix (TLM) method by special subcellular structures leading to an efficient modeling of apertures in the time domain.